Visually Induced Motion Sickness Estimation and Prediction in Virtual Reality using Frequency Components Analysis of Postural Sway Signal

The paper proposes a method for estimating and predicting visually induced motion sickness (VIMS) occurring in a navigation task in a 3D immersive virtual environment, by extracting features from the body postural sway signals in both the time and frequency domains. Past research showed that the change in the body postural sway may be an element for characterizing VIMS. Therefore, we conducted experiments in a 3D virtual environment where the task was simply a translational movement with different navigation speeds. By measuring the evolution of the body's center of gravity (COG), the analysis of the sway signals in the time domain showed a dilation of the COG's area, as well as a change in the shape of the area. Frequency Components Analysis (FCA) of the sway signal gave an efficient feature to estimate and predict the level of VIMS. The results provide promising insight to better monitor sickness in a virtual reality application.FUI Callist

Designing and defining the knowledge sharing management system between governmental organizations

The knowledge management has become important after information explosion and human's entrance into science era. Therefore, science became the most important source for organizations and countries. Science management is the process of creating value from invisible assets (Human force) of the organization. The private sector has taken the first steps to put into operation 'Science Management ‘’but the government follows the private sector with the distance of one step. However, the studies concerning sharing science out are rare as the most important part of science management process in governmental sector. This article discusses the designing of the system to share science out in governmental organizations as an essential pattern of the systems (Entrance, process, and exit). Having examined the sources concerning science management and sharing it out, our final model of the study has considered the elements important in science management frame as input in governmental sector (People, organization, technology) influencing sharing science out, the science management activities as process and finally organizational operation improvement and favorable services as the output

Feeding habits of Bigeye Houndshark, Iago omanensis (Elasmobranchii; Triakidae); a typical deep water shark from the Gulf of Oman

In this study, the feeding habits of Bigeye Houndshark, Iago omanensis, a typical deep water shark, were examined in the Gulf of Oman by analyzing of stomach contents. In addition, the effects of sex and seasons (spring and summer) on its feeding habits were evaluated. Bigeye Houndshark diet consists of mostly teleost fishes, and to a lower extent on crustaneans, molluscs and sea snakes. The great importance of teleost in the diet of Bigeye Houndshark may be due to the fact that teleosts are the dominant in terms of biomass and abundance in the area where Bigeye Houndshark exist, allowing them to exploit food resources available in the environment. No significant differences were found between sexes and seasons. This species occupy high trophic position within the food webs. These results present new data that will allow us to understand the role of Bigeye Houndshark in the deep water of Gulf of Oman to effect of fishing activity on its population dynamics in the future

The Effects of Air Pollution on Cardiovascular and Respiratory Causes of Emergency Admission

Introduction: Today, air pollution is one of the critical problems in metropolitans and necessary preparations are needed for confronting with this crisis. The present study was based on the goal of determining the relation of air pollutant levels with the rate of emergency admission for respiratory and cardiovascular patients. Methods: In the present retrospective cross- sectional study, all respiratory and cardiovascular patients, referred to emergency department during 2012, was assessed. The meteorological and pollution data were collected. Information of the numbers and dates (month, day) of daily admission of respiratory and cardiovascular diseases was achieved from hospital's electronic registration system. The relation of air pollution and respiratory and cardiovascular admissions were analyzed by Generalize additive model (GAM). Results: Totally 5922 patients were assessed included 4048 (68.36%) cardiovascular and 1874 (31.64%) respiratory disease. Carbon monoxide (CO) level was independent risk factor of cardiovascular disease on the same day (RR=1.49; 95% CI: 1.25- 1.77; P<0.001), the last day (RR=1.22; 95% CI: 1.02- 1.45; P=0.03), and the two last days (RR=1.3; 95% CI: 1.09- 1.54; P<0.001). The same process was similarly repeated for ozone (O3). In addition, the O3 level in the same day (RR=1.49; 95% CI: 1.25- 1.77; P<0.001), the last day (RR=1.22; 95% CI: 1.02- 1.45; P=0.03), the two last days (RR=1.3; 95% CI: 1.09- 1.54; P<0.001), and the last weak (RR=1.004; 95% CI: 1.0007-1.008; P=0.02) were independent risk factors of respiratory admissions. The increased level of particulate matter less than 2.5 micrometers in diameter (PM2.5) like O3 led to grow the admissions in emergency department with respiratory causes. Conclusion: The findings of the present study suggested that rising the levels of CO and O3 during two days leads to a significant increase in cardiovascular admission in the third day. Furthermore, increase the O3, PM2.5, nitrogen oxides (NO2), and CO levels causes to rising respiratory admissions in emergency department

Two-stage Robust-Stochastic Electricity Market Clearing Considering Mobile Energy Storage in Rail transportation

This paper proposes a two-stage robust-stochastic framework to evaluate the effect of the battery-based energy storage transport (BEST) system in a day-ahead market-clearing model. The model integrates the energy market-clearing process with a train routing problem, where a time-space network is used to describe the limitations of the rail transport network (RTN). Likewise, a price-sensitive shiftable (PSS) demand bidding approach is applied to increase the flexibility of the power grid operation and reduce carbon emissions in the system. The main objective of the proposed model is to determine the optimal hourly location, charge/discharge scheduling of the BEST system, power dispatch of thermal units, flexible loads scheduling as well as finding the locational marginal price (LMP) considering the daily carbon emission limit of thermal units. The proposed two-stage framework allows the market operator to differentiate between the risk level of all existing uncertainties and achieve a more flexible decision-making model. The operator can modify the conservatism degree of the market-clearing using a non-probabilistic method based on info-gap decision theory (IGDT), to reduce the effect of wind power fluctuations in real-time. In contrast, a risk-neutral-based stochastic technique is used to meet power demand uncertainty. The results of the proposed mixed-integer linear programming (MILP) problem, confirm the potential of BEST and PSS demand in decreasing the LMP, line congestion, carbon emission, and daily operation cost

Comparison of Standard and Percutaneous Tracheostomy Complications in Shariati Hospital in Iran

Background: Tracheostomy is a procedure which aims at better managing patients’ airway. It can be done using two methods: standard and percutaneous. The percutaneous method is a favorable choice for critically illpatients because it is a less invasive procedure. This study compares the short-term complications of these two methods (during 7 days after the procedure).Methods: This study was a cross-sectional research performed on 50 ICU patients in need of tracheostomy.The patients were divided into two groups of percutaneous procedure (15 patients) and standard procedure(35 patients). The complications were registered in questionnaires and the data were analyzed using SPSS software (χ² test and t-test).Results: The two groups had no significant difference in age, sex, and vital signs. Average duration of the procedure was 24.4 minutes in the standard procedure (10-45 minutes) and 26.78 minutes (5-70 minutes) in the percutaneous procedure, and there was no significant difference between two groups (P = 0.814). Average bleeding during 7 days after the procedure was 44 cc (10-150 cc) in standard procedure and 24.7 cc (10-50 cc) in the percutaneous procedure, and the difference was significant (P = 0.012). The other variables were not significantly different in two groups.Conclusions: There was no difference in short-term complications between percutaneous and standard tracheostomy method should be selected considering other important factors

Comparing Real and Virtual Object Manipulation by Physiological Signals Analysis: a first study

Virtual reality aims at reproducing reality and simulating actions like object manipulation tasks. Despite abundant past research on designing 3D interaction devices and methods to achieve close-to-real manipulation in virtual environments, strong differences exist between real and virtual object manipulation. Past work that compared between real and virtual manipulation mainly focused on user performance only. In this paper, we propose using also physiological signals, namely electromyography (EMG), to better characterize these differences. A first experiment featuring a simple pick-and-place task on a real setup and in a CAVE system showed that participants’ muscular activity reveals a clearly different spectrum in the virtual environment compared to that in reality

Features of the Postural Sway Signal as Indicators to Estimate and Predict Visually Induced Motion Sickness in Virtual Reality

Navigation in a 3D immersive virtual environment is known to be prone to visually induced motion sickness (VIMS). Several psychophysiological and behavioral methods have been used to measure the level of sickness of a user, among which is postural instability. This study investigates all the features that can be extracted from the body postural sway: area of the projection of the center of gravity (mainly considered in past studies) and its shape and the frequency components of the signal’s spectrum, in order to estimate and predict the occurrence of sickness in a typical virtual reality (VR) application. After modeling and simulation of the body postural sway, an experiment on 17 subjects identified a relation between the level of sickness and the variation both in the time and frequency domains of the body sway signal. The results support and go further into detail of findings of past studies using postural instability as an efficient indicator of sickness, giving insight to better monitor VIMS in a VR application.FUI Callist

Manifestation of Derridian Différance in Shakespeare’s Hamlet

William Shakespeare’s renowned tragedy Hamlet has ascertained itself as a touchstone for students and scholars of English literature. Extrapolating on this play, T.S. Eliot once remarked that, it is the Mona Lisa of Renaissance literature. Like Da Vinci’s painting, Hamlet (the play or the man) is a faulty or flawed work of art. Foregrounding such a literary hypothesis in mind, the present article attempts to clarify that the play’s fault, as claimed by Eliot, is not uprooted in the modern rules of decorum, construction or a reproach against image of a psychic or unaesthetic antagonist, but it is, we believe, in the postmodern concept of Différance which has been so infl uential in the assessment of literature and its values - simply articulated as the dualistic chemistry of objectifying a subjective emotion. The term Différance as a pre-postmodern quality implanted in this play, now seem to have been anachronic for the literary context of the second half of the Renaissance period. However this provides a background for Derridian term Différance which calls upon the innovative perception that differs the common perception about Hamlet.Key words: Hamlet; Flaw; Impersonalize; Dualism; DifféranceRésumé Le fameux tragédie de Hamlet de William Shakespeare est constaté lui-même comme une pierre de touche pour les étudiants et les universitaires de la littérature anglaise. En extrapolant sur ce jeu, Eliot T.S. a déjà fait remarquer que, c’est la Mona Lisa de la littérature de la Renaissance. Comme la peinture de Léonard de Vinci, Le Hamlet (le jeu ou l’homme) est un travail défectueux ou imparfait de l’art. En mettant en avant une telle hypothèse littéraire à l’esprit, le présent article tente de clarifi er que la faute de la pièce, selon Eliot, n’est pas déracinés dans les règles modernes de la bienséance, la construction ou un reproche à l’image d'un antagoniste psychique ou inesthétique, mais il est , nous croyons, dans le concept postmoderne de la différance qui a eu une telle infl uence dans l’évaluation de la littérature et de ses valeurs, vous n’avez qu’à articulé que la chimie dualiste d’objectiver une émotion subjective. La différance terme comme une qualité pré-post-moderne implanté dans cette pièce, semblent maintenant avoir été anachronique dans le contexte littéraire de la seconde moitié de la période de la Renaissance. Cependant, cette offre un arrière-plan pour différance derridienne terme qui fait appel à la perception novatrice qui diffère de la perception commune à propos de Hamlet.Mots clés: Hamlet; Défauts; Impersonalize; Dualisme; Différanc